(Adapted from the Applicant?s Abstract) The Division of Clinical Care Research, and its Biostatistics Research Center led by Drs. Harry Selker and John Griffith will function as the Statistical Core for this proposed SCOR program. The Statistical Core will be available to provide statistical support to all five projects. The large majority (80%) of the effort of the Statistical Core will go to supporting the clinical trial (SCOR Project 2, J. Udelson PI, M. Konstam, Co-PI). Statistical Core staff will be involved in all aspects of the experimental design of the study and creation of necessary forms, and will provide full support for the creation and maintenance of the primary trial databases. These data will be stored on a shared drive, with access limited to the statistical staff of the center and the data entry personal. As done in their previous prospective clinical trials, the staff of the Biostatistics Research Center will provide data quality and consistency checks continuously through-out the trial. During these data checks randomization codes will not be present. All data will be backed-up nightly and at regular intervals copies will be stored off-site. For confidentiality no specific patient identifiers will be stored on the electronic datasets stored on these drives. The staff of the Statistical Core will provide general oversite, utilizing the extensive experience of the staff in running clinical trials.